Railway traffic controlling apparatus



May 11, 1934. c. A. BROOKS ET AL RAILWAY TRAFFIC CONTROLLING APPARATUS Filed Oct. 9, 1929 INVENTORS. amBr-wks, JTM.PJ;/ 4n,

mag-W Fatented May 1, 1934 Ni'lE STATES PATENT OFFICE RAILWAY TRAFFIC CONTROLLING APPARATUS Application October 9, 1929, Serial No. 398,361

9 Claims.

Our invention relates to railway traffic controlling apparatus, and particularly to apparatus comprising a railway track switch and a signal directing traffic movements over the switch. More particularly, our invention relates to the approach locking of such switch when a train enters a track section adjacent the signal while the signal is indicating proceed.

One feature of our invention is the provision of means controlled by a signal and by traffic conditions for releasing the approach locking of a switch after the lapse of a measured period of time.

We will describe one form of apparatus embodying our invention, and will then point out the novel features thereof in claims.

The accompanying drawing is a diagrammatic view showing one form of apparatus embodying our invention.

Referring to the drawing, reference characters 1 and 1 designate the track rails of a stretch of railway track including a switch F. This stretch of track is divided by insulated joints 2 into sections AB and BC. Section A-B will be referred to hereinafter as an approach section, and section 3-0, in which switch F is located, will be referred to as a detector section. Each of these track sections is provided with a track circuit including a battery 3 connected across the rails adjacent one end of the section, and a track relay designated by the reference character R with a distinguishing exponent and connected across the rails adjacent the opposite end of the section.

Trafic moving from left to right, as shown in the drawing, over switch F, is governed by a signal designated by the reference character S. Signal S operates a contact 5 which is closed when and only when signal S indicates stop. As here indicated, signal S is of the semaphore type, although our invention is not limited to this form.

Switch F may be operated by any suitable means such, for example, as an electric motor M which, as shown in the accompanyiny drawing, comprises an armature l8 and a field winding 21. In conjunction with switch F, motor M operates a contact member 20 which connects with a segment 20 at all times except while switch F is in its normal position, and which connects with a segment 20 at all times except while switch F is in its reverse position.

Motor M is provided with operating circuits which include contacts of a polarized relay P. Motor M moves switch F to its normal or its reverse position according as polar contacts of relay P are closed in their normal or their reverse position.

Relay P may be controlled by any suitable means such, for example, as a lever in a train dispatchers office operating a contact included in a circuit for relay P, only a portion of which is shown, including a front contact 14 of an approach locking relay L and a front contact 22 of relay R Relay L is provided with pick-up and stick circuits, each of which includes contact 5 of signal S. There are three pick-up circuits for relay L controlled by relays R R and a time element device 1-1, respectively, as well as by contact 5 of signal S.

Time element device H, as here shown, is of the thermal relay type but may be of any other suitable type. Thermal relay H comprises a heater element 15 and a contact 10 which closes when and only when heater element has been 7 energized for a measured period of time which may vary within certain limits.

A battery Q supplies energy for operating relays H and L and switch motor M.

As shown in the drawing, all parts are in their normal condition, that is, sections A-B and BC are unoccupied, relay P is energized in the normal direction, switch F is in its normal position, and signal S is indicating stop. A pick-up circuit for relay L is closed passing from battery Q, through wire l, contact 5 of signal S, contact 6 of relay R winding of relay L, and common wire 13 back to battery Q. A stick circuit for relay L is also closed passing from battery Q, through wire l, contact 5 of signal S, wires 7, 9 and 11, contact 12 of relay L, winding of relay L, and wire 13 back to battery Q.

We will now assume that an eastbound train, that is, a train moving from left to right as shown in the drawing, enters section A--B, deenergizing relay R which then opens its contact 6 in the pick-up circuit already traced for relay L. Relay L, however, continues energized by its stick circuit which has also already been tracedv With relay L still energized, its contact 14 remains closed in the control circuit for relay P, and hence, if the dispatcher should now so desire, he could supply relay P with current of reverse polarity for controlling the operation of switch F to its reverse position.

If relay P were now thus supplied with current of reverse polarity, its contacts 17 and 19 would be moved to their reverse position. Motor M would, therefore, be supplied with current through its reverse operating circuit passing from battery Q, through contact 16 of relay P, contact 19 of relay P closed in its reverse position, armature 18 of motor M, contact 1'7 of relay P closed in the reverse position, contact 20 2o of switch F, field winding 21 of motor M, and wire 13 back to battery Q. Motor M would now move switch F to its reverse position. Just before reaching the reverse position, contact 20 -2O of switch F would open, breaking the circuit for motor M.

When the dispatcher later desires to return switch P to its normal position, he energizes relay P in the normal direction causing contacts 17 and l to be moved to their normal position. Motor M is now supplied with current for operating switch F to its normal position by a circuit passing from battery Q, through contact 16 of relay P, contact 17 of relay P closed in its normal position, armature 18 of motor M, contact 19 of relay P closed in its normal position, contact 20 20 of switch F, field winding 21 of motor M, and wire 13 back to battery Q. Contact 20 -20 opens just before switch F reaches th normal position, thereby breaking the circuit for motor M.

We will now assume that all parts are again in their normal condition, and that the dispatcher clears signal S for a train to proceed over switch F. When the arm of signal S leaves its stop position, its contact 5 opens the pick-up and stick circuits previously traced for relay L. If, now, the dispatcher should return the arm of signal S to its stop position before a train enters section A-B, relay L will be again energized by its pick-up circuit already traced. Relay L, upon closing its contact 12, again completes its stick circuit.

We will next assume that all parts are again in their normal condition, and that the dispatcher operates the arm of signal S to its proceed position thereby causing the pick-up and stick circuits for relay L to be opened at contact 5 of signal S. We will also assume that an eastbound train, moving through section AB, enters section BC. If the dispatcher now returns the arm of signal S to its stop position, a second pick-up circuit for relay L will be closed passing from battery Q, through wire 4, contact 5 of signal S, wire '7, contact 8 of relay R winding of relay L, and wire 13 back to battery Q. Relay L then becomes energized and closes its contact 12= thus completing its stick circuit already traced. Relay P, however, continues de-energized as long as the train is in the section B-C and is causing contact 22 of relay R to remain open.

When the train moves out of section AB, the pick-up circuit first traced for relay L becomes completed at contact 6 of relay R With relay R energized when the train leaves section 3-0, the circuit for relay P is again completed at contact 22 of relay R All parts are therefore again in their normal condition.

We will next assume that with all parts again in their normal condition, the dispatcher again clears signal S and that an eastbound train then enters section AB. With signal S indicating proceed, the pick-up and stick circuits for relay L are open at contact 5 of signal S, and hence the circuit for relay P is open at contact 14 of relay L. If, now, the dispatcher returns the arm of signal S to its stop position before the train enters section B-C, relay L continues de-energized, and hence, as soon as contact 5 of signal S closes, a circuit is completed for thermal relay H passing from battery Q, through wire 4, contact 5 of signal S, wires 7, 9 and 11, contact 12 of relay L, heater 15 of relay H, and wire 13 back to battery Q. After the lapse of a period of time which may have any value within given limits, contact 10 of relay Pi picks up and completes a third pick-up circuit for relay L passing from battery Q, through wire 4, contact 5 of signal S, wires 7 and 9, contact 10 of relay H, winding of relay L, and wire 13 back to battery Q. Relay L, upon becoming energized, closes its contact 12 thereby completing its stick circuit previously traced. The circuit for heater 15 of relay H is now open at contact 12 of relay L. Relay L now continues energized by its stick circuit, and hence the dispatcher can, if he so desires, now operate switch F to the reverse position.

From the foregoing description and the accompanying drawing, it is clear that, with apparatus embodying our invention, if the dispatcher returns the arm of signal S to its stop position while a train is in section AB, he can, after the lapse of a measured period of time, and without any separate manual releasing operation, re-

verse the switch if he so desires.

Although we have herein shown and described only one form of railway traffic controlling apparatus embodying our invention, it is understood that various changes and modifications may be made therein within the scope of the appended claims without departing from the spirit and scope of our invention.

Having thus described our invention, what we I claim is:

1. Ln combination, a railway track switch, a

controlled by said signal and which is closed i:

when and only when said signal indicates stop, a pick-up circuit for said stick relay including said signal-controlled contact and a front contact of said track relay, a stick circuit for said stick relay including said signal-controlled contact, a time element device having a contact which closes when and only when said time element device has been energized for a measured period of time, a control circuit for said time element device including a back contact of said stick relay and said signal-controlled contact, a second pick-up circuit for said stick relay including said time element device contact and said signal-controlled contact, a detector track section for said switch including a track relay, a third pick-up circuit for said stick relay includ-- ing said signal-controlled contact and a back contact of said detector track section relay, and an operating circuit for said switch controlled by said stick relay.

2. In combination with a main section and an approach section of railway track, a switch in said main section, a signal for governing traific over said switch, mechanism for operating said switch, locking means for preventing operation of said mechanism if said approach section is occupied while said signal indicates proceed, a time element device set into operation if the sig nal is restored to the stop condition while said approach section is occupied, and means contraffic movements over said switch, a contact mechanically operable by said signal, a time ele ment device controlled by said contact, a second relay controlled by said contact and by a front contact of said track relay as well as by said time element device, and means controlled by said second relay for controlling said switch.

4. In combination, a stretch of railway track comprising a first section and a second section, a track switch included in said first section, a signal for governing trafiic movements over said switch, mechanism for operating said switch, locking means for preventing operation of said mechanism if said signal indicates proceed, a time element device set into operation if the signal is restored to the stop condition while said first section is unoccupied and said second section is occupied, and means controlled by said time element device for releasing said locking means.

5. In combination, a railway track switch, a signal having an indication element for directing traific movements over said switch, a track section adjacent said signal, a track circuit for said section including a track relay, a time element device controlled by said indication element, a second relay controlled by said indication element and by said time element device and so controlled by said track relay that it is at times energized only if said track relay is energized, and means controlled by said second relay for controlling said switch.

6. In combination, a stretch of railway track including a switch, a track circuit for said stretch including a track relay, a signal having an indication element for directing traffic movements over said switch, a time element device controlled by said indication element, a second relay controlled by said time element device and so controlled by said track relay as to at times be energized only if said track relay is energized, and

means controlled by said second relay for con trolling said switch.

7. In combination, a stretch of railway track including a switch, a track circuit for said stretch including a track relay, a signal for governing traiiic movements over said switch, a contact mechanically operable by said signal, a time element device controlled by said contact, a second relay controlled by said time element device and so controlled by said track relay as to at times be energized only if said track relay is energized, and means controlled by said second relay for controlling said switch.

8. In combination, a railway track switch, a

ignal for governing traiiic movements over said switch, a track section adjacent said signal, a track circuit for said section including a track relay, a second relay, a time element device, a circuit including a contact operated by said signal for energizing said time element device, means controlled by said time element device for controlling said second relay, means controlled by said track relay for at times energizing said second relay only if said track relay is energized, and means controlled by said second relay for controlling said switch.

9. In combination, a railway track switch, a signal having an indication element for directing traffic movements over said switch, a track circuit adjacent said signal, a release relay controlled by said indication element to become energiaed only if said signal indicates stop, an approach locking relay controlled by said release relay and so controlled by said track circuit as to at times be energized only if said track circuit is energized, and means controlled by said approach locking relay for controlling said switch.

CHARLES A. BROOKS. JOHN M. PELIKAN. 

